1. Technical Field
The present invention relates to a power package module and a method for fabricating the same.
2. Description of the Related Art
Generally, a semiconductor package includes a single or a plurality of semiconductor chips mounted on a lead frame or a printed circuit board and has the inside thereof protect by sealing them with a sealing resin, and is then coupled with a mother board or a printed circuit board for a system.
However, with the recent rapid progress of a high-speed, high-volume, and high-integration of electronic equipment, there is a demand for compact and light power device used in automobiles, industrial equipment, and home appliances at low costs. One method to meet the demand is to configure a power module package using a method of mounting a plurality of semiconductor chips on a single semiconductor package. The power module package includes a power circuit chip and a control chip and in particular, the power circuit chip generates more heat as compared to other semiconductor chip. Therefore, effective radiation of the generated heat to the outside becomes an important issue in order to maintain high reliability for a long period.
FIG. 1 is a cross-sectional view of a power package module 100 according to the prior art. As shown in the figure, a power package module 100 according to the prior art is configured to include a base substrate 110, a high power chip 120, a low power chip 130, a housing 140, and a molding part 150.
The base substrate 110 is configured to include a metal layer 111, an anodizing layer 112, and a circuit layer 113. More specifically, the anodizing layer 112 is formed on the surface of the metal layer 111 by anodizing the metal layer 111 and then the circuit layer 113 is formed on the anodizing layer 112, thereby fabricating the base substrate 110. In addition, the circuit layer 113, a solder layer 180, and a high power chip 120 and a lower power chip 130 electrically connected through wires 143 and 144 are formed on the base substrate 110.
The housing 140 is formed to surround side surfaces of the base substrate 110, and a lead 141 connected to the circuit layer 113 of the base substrate 110 through a wire 142 is formed in the housing 140. In addition, a molding part 150 for fixing and protecting the base substrate 110 is formed in the housing 140 and a cover 160 is formed on the upper portion of the molding part 150.
However, in the power package module 100 according to the prior art, thermal stress generated from the high power chip 120 and the low power chip 130 is transferred to the base substrate 110 in a vertical direction through the solder layer 180, such that warpage of the base substrate 110 is caused by thermal conductivity. As a result, a problem arises in that the anodizing layer 112 as well as the base substrate 110 are bent or distorted.
In addition, when fabricating the high power package module 100, at least two to ten or more wires should be connected for each chip, such that a long period of process operation is required.